TY - JOUR
T1 - Biofilm formation by ESBL-producing strains of Escherichia coli and Klebsiella pneumoniae
AU - Surgers, Laure
AU - Boyd, Anders
AU - Girard, Pierre Marie
AU - Arlet, Guillaume
AU - Decré, Dominique
N1 - Funding Information: Laure Surgers received funding from the Fondation pour la Recherche Médicale ( DEA20140630021 ). Anders Boyd received post-doctoral funding from SIDACTION for part of the work presented herein. No funding of any kind has been received for this study. Publisher Copyright: © 2018 Elsevier GmbH
PY - 2019/1
Y1 - 2019/1
N2 - Objectives: Biofilm production in extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae provides a favourable environment for the exchange of antibiotic-resistance genes and could facilitate widespread dissemination. We aimed to assess biofilm development in ESBL-producing E. coli and K. pneumoniae isolates and determine how development relates to microbiological characteristics and clinical outcomes. Methods: 147 ESBL-producing E. coli and 82 K. pneumoniae were genetically characterized. Biofilm formation was measured at 1.5, 4, 6, and 24 h during culture in blood heart infusion using a microbead immobilization assay (BioFilm Ring test®). Results were given as biofilm formation index (BFI) with lower values indicating increased presence of biofilm (range = 0–21). Results: In total, 57.1% of strains were strong producers of biofilm (BFI < 2), whereas 13.4% lacked biofilm production (BFI > 18). Standard biofilm production (BFI < 7) was common in E. coli isolates (61.9%). For E. coli, biofilm production was less frequently observed in ST131 clones (p = 0.03) but more frequently in strains harbouring toxin (p = 0.008) or adhesin (p = 0.008) virulence factor genes. Despite almost all K. pneumoniae having standard biofilm production (90.2%), there was a 2.4-times higher odds of observing biofilm in ST29/147/323 versus other ST-types (p = 0.13). Patients with standard biofilm producing isolates were not at increased risk of transfer to intensive-care (odds-ratio=2.80, 95%CI=0.59–13.21) or death within 12-months (odds-ratio=1.61, 95%CI=0.75–3.43). Conclusion: In these ESBL-producing strains, biofilm production is linked to certain virulence factors in E. coli and is common in K. pneumoniae. Further exploration of whether biofilm production increases dissemination and risk of severe clinical outcomes is needed in larger collections of isolates.
AB - Objectives: Biofilm production in extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae provides a favourable environment for the exchange of antibiotic-resistance genes and could facilitate widespread dissemination. We aimed to assess biofilm development in ESBL-producing E. coli and K. pneumoniae isolates and determine how development relates to microbiological characteristics and clinical outcomes. Methods: 147 ESBL-producing E. coli and 82 K. pneumoniae were genetically characterized. Biofilm formation was measured at 1.5, 4, 6, and 24 h during culture in blood heart infusion using a microbead immobilization assay (BioFilm Ring test®). Results were given as biofilm formation index (BFI) with lower values indicating increased presence of biofilm (range = 0–21). Results: In total, 57.1% of strains were strong producers of biofilm (BFI < 2), whereas 13.4% lacked biofilm production (BFI > 18). Standard biofilm production (BFI < 7) was common in E. coli isolates (61.9%). For E. coli, biofilm production was less frequently observed in ST131 clones (p = 0.03) but more frequently in strains harbouring toxin (p = 0.008) or adhesin (p = 0.008) virulence factor genes. Despite almost all K. pneumoniae having standard biofilm production (90.2%), there was a 2.4-times higher odds of observing biofilm in ST29/147/323 versus other ST-types (p = 0.13). Patients with standard biofilm producing isolates were not at increased risk of transfer to intensive-care (odds-ratio=2.80, 95%CI=0.59–13.21) or death within 12-months (odds-ratio=1.61, 95%CI=0.75–3.43). Conclusion: In these ESBL-producing strains, biofilm production is linked to certain virulence factors in E. coli and is common in K. pneumoniae. Further exploration of whether biofilm production increases dissemination and risk of severe clinical outcomes is needed in larger collections of isolates.
KW - Biofilm kinetics
KW - Biofilm production
KW - ESBL-producing enterobacteriaceae
KW - Escherichia coli
KW - Klebsiella pneumoniae
UR - http://www.scopus.com/inward/record.url?scp=85055529032&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.ijmm.2018.10.008
DO - https://doi.org/10.1016/j.ijmm.2018.10.008
M3 - Article
C2 - 30385204
SN - 1438-4221
VL - 309
SP - 13
EP - 18
JO - International journal of medical microbiology
JF - International journal of medical microbiology
IS - 1
ER -